Automatic cut-out for electric heaters.



W. S. ANDREWS. AUTOMATIC GUT-OUT FOR ELECTRIC HEATERS.

APPLICATION FILED JAN. 18, 1910. 1,025,852. Patented May 7, 1912.

2 SHEETS-SHEET 1.

i I E =1 l Z 2f Fig. 2.

Witnesses: Inventor William S. findrews,

W. S. ANDREWS. AUTOMATIC GUT-OUT FOR ELECTRIC HEATERS.

APPLICATION FILED JAN.18, 1910.

1,025,852, Patented May 7, 1912.

2 SHEETS-SHEET 2.

munuum mmmuu n mypx Witnesses Inventor ,4 Wil Ham SJIndrews,

bg MM UNITED STATES PATENT OFFICE.

WILLIAM S. ANDREWS, 0F SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY A CORPORATION OF NEW YORK.

AUTOMATIC COT-OUT FOB ELECTRIC HEATERS.

Specification of Letters Patent.

. Patented Ma "2, 1912.

Application filed January 18, 1910. Serial No. 538,739.

To all whom it may concern:

Be it known that I, VILLIAM S. ANDREWS,

a citizen of the United States, residing at Schenectady, county of Schenectady State of New York, have invented certain new that some means be provided whereby the" heat will be cut oil from the iron in case the temperaturekexceeds a predetermined de-' One of the objects of'my invention is to provide, in connection with an automatic switch for cutting out the heating unit, means for again closing the switch as Well as means whereby the switch may be opened by the operator at any time.

I also provide mechanism for positively latching the switch closed and so arrange the parts that a wide quick break will be given so as to open the circuit effectively and without injury to the switch due to excessive arcing at the contacts.

. sents a perspective view of the switch and Other objects of my invention will appear in the course of the following specification in which I have shown my invention embodied in concrete form for purposes of illustration. i

In the drawings disclosing one form of my invention, Figure 1 represents a side view of the same, partly broken away to show the operating mechanism; Fig. 2 represents a plan view of the iron with the up per portion removed, the parts of the switch being shown inclosed position; Fig. 3 representsa-view similar to Fig. 2 with the switch in open position; and Fig. 4 reprethe circuit connections.

Referring to the drawing, 10 represents the body of the iron, which may be of any desired material, such, for instance, as cast iron. The particular shape and construction of this iron, as far as the heating arrangement is concerned, formsno part of my invention. The heating element may be of any well-known'type.

Mounted upon the body of'the iron is a switch comprising two contacts 11 and 12 which may be of platinum and when in contact with each other complete the circuit of the electric heater. The contact 11 is mounted upon the resilient metal bar 13. The contact 12 is likewise mounted upon the resilient bar or strip 1 1.

flat iron, Whereas the end supporting the contact 12 is free to move toward and from the contact 11. This resilient strip 14 is preferably made of such'material that it may be heated to a considerable temperature without destroying the resiliency. Normally the contacts 11 and 12 are separated from each other, as shown. in Fig. 3.

Mounted longitudinally of the flat iron is a thermostatic element '15. This element maybe constructed in any desired manner. I have shown the well-known compound bar type of thermostat which, when heated, will bend due to the diiference in the coefiicient of expansion of the metals composing it. One end of the thermostatic element is fixed to the body of the heater by screws 16, and

the opposite end is free to move with changes of temperature. The free end of this member is adapted to act as a latch for locking switch contacts 11 and 12 in closed position. The latching mechanism comprises a beveled portion 17 on the end ofthe bar which is adapted to be engaged by a similarly beveled locking, bar or bolt 18, preferably of hardened tool steel. This bolt 18 is fixedly mounted in a member 19 pivoted to the body of the iron at 20. The bolt is mounted about midway of the member 19 and the free end of the member is adapted to engage a block of insulating material 21 on the end of the strip 14 adjacent contact 12. The arrangement is such that whenthe .member 19 is turned on its axis, the insulating block 21 is engaged by the end of the.

One end of this strip is securely fastened to the body of the rection.

This rod 24 projects upward in front. of the handle of the iron and is held in place by a guide 26.. A spring 27, one end of which 1s secured to the rod, while the other end is secured to the fixed part of the handle, gives the rod a tendency to turn in a direction to open the switch, or in a counterclockwise d1- On the upper end of the rod 24 is a handle 28 for turning the rod toclose the switch.

In order to manually open the switch at any time, I have provided a push button 29 the shank of which projects through the cover of the iron so that the end engages the thermostatic element L5. This push button 29 is arranged conveniently near the handle of the fiat iron so that the operator may, by simply pressing a button, force the thermostatic element down and trip the latch, thereby opening the circuit of contacts 11 and 12. A set screw 30 is arranged to adjust the thermostat for various temperatures if desired.

The operation of my device will be very easily understood from the foregoing description. If the temperature exceeds a predetermined degree, the thermostatic element will bend and trip the latch, the spring 27 operating to quickly turn member 19 away from the block 21 to open the switch contacts. In order to again close the switch, the handle 28 is turned. Of course the switch cannot be latched closeduntil the iron is cooled ofl sufliciently to permit the thermostatic element to get back to its normal condition. If at any time it is desired to open the circuit without waiting for the iron to reach a predetermined degree of heat, the push button is operated. The circuit will, of course, again be closed by turning the handle 28.

It will be seen that I have provided a very simple arrangement whereby the current may be cut off either automatically or manually and may be again turned on by the operator in a simple manner. The construction is such as to cause a wide quick break to prevent injurious arcing at the contacts.

I have shown my invention embodied in concrete mechanism for purposes of illustration, in accordance with the patent statutes, but it should be understood that I do not limit my invention to the particular construction or arrangement of parts herein described, except in so far as they are limited by the scope of the annexed claims,

since various modifications of my invention will suggest. themselves to those skilled in the art without departing from the spirit of my invention.

\Vhat I claim as new and desire to secure by Letters Patent of the United States, is

1. The combination with an electric heater, of a normally open switch in the circuit thereof, a thermostatic element for .latching said switchclosed and releasing the same at a predetermined temperature, and means controlled by the operator for releasing the latch.

2. The combination with an electric heater, of a normally open switch in the circuit thereof, a thermostatic element for latching said switch closed and releasing the same at a predetermined temperature, and means controlled by the operator for actuating the thermostatic element to release the latch.

3. The combination with an electric heater, of a normally open switch in the circuit thereof, a thermostatic element for latching said switch closed, manually operated means for moving the switch to latching position and. independent manually operated means for releasing the latch.

4. The combination with an electric heater, of a switch in the circuit thereof biased to open position, a resilient thermostatic element, and means for latching said switch in closed position comprising a beveled member on the thermostatic element and a similarly beveled member associated with the switch.

5. The combination with an electric heater of a switch in the circuit thereof biase to open position, a thermostatic element, and beveled latching mechanism between the thermostatic member and the switch.

6. The combination with an electric flat iron, of a switch in the circuit thereof biased to open position, a thermostatic element, latching mechanism between the thermostatic member and the switch, manually operated mechanism for moving the parts to latching position, and manually operated mechanism for moving the thermostatic member to release the, latch.

7. The combination with an electric flat iron, of a normally open switch in the circuit thereof, a thermostatic element, latching mechanism between the switch and said element, a rotary member for moving the switch to latching position, and a button adjacent the handle for tripping the latch.

8. The combination with an electric flatiron, of a normally open switch in the circuit thereof, a thermostatic element, beveled latching mechanism between the switch and said element, a manually operated member for moving the switch to latching position, and a push button for operating the thermostatic member to trip the latch.

9. The combination with an electric flat- 10. The combination with an electric flatof a normally open switch in the cirdevice for holdin a member a iron, cuit thereof, a latching the switch in closed position,

iacent the handle of the flatiron for'latching; the switch closed, and inde endent means located so as to be operated rom the top of the flatiron for releasing the latch. 15 In witness whereof, I have hereunto set my hand this 17th day of January, 1910.

WILLIAM ,S. ANDREWS.

Witnesses:

BENJAMIN B. HULL, HELEN Onronn. 

